The present invention relates to the field of viscous liquid dispensers, for example soap dispensers.
Various configurations and models of liquid dispensers, particularly liquid soap dispensers, are well known in the art. Conventional dispensers typically employed in public restrooms and the like are wall mounted units that typically include a house or structure that is permanently affixed to a wall. These dispensers typically include an access door or member so that the dispenser can be opened by a maintenance person for refilling or servicing. With certain types of dispensers, separate refill cartridges are inserted into the housing structure. With other types of dispensers, the maintenance technician must directly refill a reservoir provided in the housing structure. The dispensers typically include a delivery device, such as a dosing pump, and a device such as a lever or button for actuating the dosing pump. The dispensers may be vented or unvented.
The conventional dispensers depend on the continued maintenance and operability of the housing structure that is permanently affixed to the wall. In other words, if the housing structure, and particularly the dosing pump, is damaged or vandalized, the dispenser becomes inoperable and must be replaced. The conventional dispensers also depend on a supply system wherein additional liquid soap must be separately stored, transported, and loaded into the dispensers. This process entails unnecessary logistic and man power resources.
The present invention is an improvement over existing systems in that it provides a disposable self-contained dispenser with a significantly increased capacity as compared to standard dispensers, is relatively inexpensive, and does not depend on the separate storage and delivery of refill cartridges or bulk volumes of liquid soap.
Objects and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention.
The present invention provides a self-contained viscous liquid dispenser. Although having particular usefulness as a liquid soap dispenser, the dispenser according to the invention is not limited to a liquid soap dispenser and may be utilized in any application wherein it is desired to dispense metered doses of a viscous liquid. The liquid dispenser will be described herein with reference to a soap dispenser for ease of explanation.
The viscous liquid dispenser includes a housing that may be formed of any suitable material. For example, the housing may be molded from relatively inexpensive plastic materials and may have any desired aesthetic shape. The housing also defines an integral sealed internal liquid reservoir. In other words, the liquid reservoir is not a separate component from the housing, such as a cartridge or the like. The housing may be comprised of wall members that give the dispenser its outward appearance and also define the internal liquid reservoir.
A dispensing pump mechanism is disposed at least partially within the reservoir. The pump mechanism has a delivery end that extends out of the reservoir which is actuated by a user to dispense the viscous liquid.
The dispenser also includes a mounting mechanism that is configured as an integral component of the housing. The mounting mechanism allows the dispenser to be detachably connected to complimentary mounting structure on a wall surface. In this way, the dispenser may be easily removed from the wall surface for disposal or recycling once the liquid has been depleted. A new liquid dispenser according to the invention is then attached to the wall surface.
In one embodiment of the invention, the housing comprises a substantially vertical back side that is configured to be placed adjacent to the wall surface. The mounting mechanism is configured in the back side. For example, if the housing is a molded component, the mounting mechanism is molded integral with the back side. The mounting mechanism may comprise a recess that is defined in the back side. The recess may be defined by side walls that have engaging structures defined thereon. These engaging structures interlockingly engage with complimentary structure provided on the wall mounting structure. The wall mounting structure may be, for example, a plate member or similar device that is relatively permanently affixed to the wall. In one embodiment of the engaging structure, the vertical side walls of the recess include at least one angled surface on each vertical side wall. These angled surfaces engage against complimentary angled surfaces on the mounting wall structure similar to a conventional dove-tail configuration. The housing is slidable in a generally vertical direction onto the wall mounting structure so that the angled surfaces of the mounting mechanism slide into engagement against the angled surfaces of the wall mounting structure. Once engaged, the angled surfaces prevent the dispenser from being pulled away from the wall mounting structure. A securing device may be provided on the back side of the housing to prevent relative sliding movement between the housing and the wall mounting structure upon engagement of the angled surfaces. This securing device may be, for example, a simple protrusion disposed on the back side of the housing that engages in a complimentary recess or divot defined in the wall mounting structure.
In one particularly useful embodiment, at least two spaced apart angled surfaces are provided on each vertical wall of the recess that engage against complimentary spaced apart angled surfaces on the wall structure. The spaced apart configuration of the angled surfaces maximizes the surface contact area between the housing and the wall mounting structure without significantly increasing the relative sliding distance between the members.
As mentioned, the housing structure is preferably formed from a relatively inexpensive molded plastic and may comprise separately molded components that are permanently affixed or adhered to each other. For example, the housing may include a front component that is formed separately from and adhered to a back component. It may be desired that the front and back components have different characteristics. For example, it may be desired that the back component is more rigid than the front component to provide enhanced structural support and rigidity to the dispenser mounted on the wall structure. This may be accomplished by simply making the back component thicker than the front component.
It may also be desired to make at least a portion of the housing translucent or clear so that a maintenance technician can easily determine the remaining level of liquid within the reservoir. For example, a window may be provided in the housing. In one particularly useful embodiment, the housing includes a back component that is formed from a translucent material so that the entire volume of the reservoir is visible from the outside.
Any manner of actuator may be provided with the dispenser to allow the user to operate the pump mechanism. For example, in one embodiment, the actuator may comprise a panel member that contributes to the aesthetic appearance of the housing. The panel member may be hinged or otherwise movably connected to the housing member and lie in contact against a delivery end of the pumping mechanism. Upon the user depressing or moving the panel, the pumping mechanism is actuated so that a metered dose of the liquid is dispensed. In an alternate embodiment, the actuator may comprise a member, such as a decorative cap or the like, directly attached to the delivery end of the pump mechanism. In other words, the actuator need not be connected directly to the housing. Various embodiments of aesthetically pleasing actuators may be used in this regard.
The pump mechanism may include a pump chamber that is formed integral with the housing within the reservoir. For example, the housing may comprise a molded plastic component wherein a pump chamber is integrally molded on the interior of the housing. The pump chamber has a back end that is open to the reservoir section of the housing and a front end that is open to the outside of the housing. A pump cylinder is slidably disposed and retained in the chamber. The pump cylinder has a channel defined therethrough and a delivery end extending out of the front end of the chamber. The pump cylinder is retained within the chamber so that it cannot be pulled therefrom. An actuator is configured with the delivery end of the pump cylinder so that the device may be actuated by a user from outside of the housing. A valve mechanism is disposed in the delivery end of the pump cylinder and is configured to close upon the user releasing the actuator to prevent leakage or dripping of liquid from the pump cylinder.
In one embodiment, the pump cylinder is insertable into the pump chamber from its back end. The chamber includes retaining structure, such as a flange member or the like, at its front end to prevent withdrawal of the pump cylinder from the pump chamber through the front end. A cap member or like device is attached to the back end of the pump chamber once the cylinder has been inserted into the chamber. The cap member has an orifice defined therethrough for drawing liquid into the pump chamber. A check valve device, such as a shuttle valve, is disposed in the orifice to close the orifice upon actuation of the pump cylinder.
The valve mechanism disposed in the delivery end of the pump cylinder may comprise a flexible flap member that is movable to an open position by the pressure of the liquid being dispensed. Upon release of the actuator, the flap member automatically returns to a closed position and thus prevents undesired leakage or drippage of the liquid out of the delivery end of the pump cylinder. In one particularly useful embodiment, the valve mechanism comprises a plurality of flap members that define an opening therethrough in their open position, and seal against each other in their closed position.
A vent path is defined into the reservoir to prevent drawing a vacuum therein. In a particularly desired embodiment, the vent is provided in a top surface of the housing structure. Since the housing structure is mounted in use upon a wall surface, there is little concern of the liquid leaking from the vent in the top surface. In other embodiments, the reservoir may be vented through the pump mechanism. However, venting through the pump mechanism may result in undesired leakage through the mechanism, particularly if the pump mechanism is disposed in the lower portion of the housing. Venting may also be accomplished through the valve mechanism in the delivery end of the pump cylinder.
It should be appreciated that the configuration and appearance of the housing is not a limiting feature of the invention. Also, the invention is not limited to the use of any particular type of materials or manufacturing process. Various embodiments of interlocking engagement structure between the back side of the housing and the wall mounting member are also within the scope and spirit of the invention. For example, the engaging structure may include bayonet type fasteners, or the like.
In an alternate embodiment of a pump mechanism that may be used in a dispenser according to the invention, an insert member is inserted through an opening defined in a front surface of the housing. The insert member extends into the reservoir and defines an internal pump chamber having a back end open to the reservoir and a front end open to the outside of the housing. The insert member is attached to the housing at the opening by any suitable mechanism. In one particular embodiment, the housing comprises a plurality of protrusions extending from the front surface and disposed around the opening. The insert member comprises a front flange having a plurality of counter-bored holes defined therethrough into which the protrusions extend upon mounting the insert member into the housing. The protrusions are then heated to a molten state wherein the protrusion material flows into the counter-bored holes and permanently affixes the insert member to the housing upon re-solidifying. If it is desired to recycle or reuse the pump mechanism, a less permanent or temporary type of attachment mechanism may be used to affix the insert member to the housing, such as a releasable adhesive, mechanical connection (i.e., threaded engagement), etc.
At least one seal is disposed between an outer surface of the insert member and the housing to ensure that liquid within the reservoir does not leak out from around the insert member. In one particular embodiment, this seal is a radially inward extending seal disposed around the opening in the housing that engages and seals against an outer surface of the insert member. This seal may be provided on a cylindrical extension of the housing that extends from the front surface into the reservoir. In an alternate embodiment, the seal may be a radially outward extending seal disposed at a forward end of the insert member that engages and seals against a portion of the housing defining the opening. It may be desired to use both types of seals in the same embodiment.
An alternative embodiment of a pump cylinder that may be used with an integrally formed pump chamber or pump chamber insert is also provided. This pump cylinder may include multiple components. For example, in one embodiment, the pump cylinder includes a first component and a second component inserted into a chamber defined in the first component. Longitudinally extending channels in the components align to define a delivery channel through the pump cylinder. This channel terminates at a delivery orifice defined in a delivery end of the pump cylinder. Once combined, the components define a complete pump cylinder that is slidable within the pump chamber from a rest position to a pressurizing position wherein liquid drawn into the pump chamber is pressurized and dispensed through the delivery channel and out the dispensing orifice.
In order to seal the pump cylinder relative to the pump chamber, a first radially extending seal, such as a flange seal, may be provided on the first component of the pump cylinder that slidably engages along a wall defining the pump chamber. A second similar seal may be provided on the second component that also slidably engages along the pump chamber wall.